zephyr/samples/subsys/nvs
Marc Herbert 2cd51a33ce samples: make find_package(Zephyr...) REQUIRED
This provides a better error message when building with CMake and
forgetting ZEPHYR_BASE or not registering Zephyr in the CMake package
registry. See parent commit for more details (split from parent for
better readability).

Signed-off-by: Marc Herbert <marc.herbert@intel.com>
2020-05-29 10:47:25 +02:00
..
src flash: Convert DT_FLASH_AREA to FLASH_AREA macros 2020-05-13 21:22:53 +02:00
CMakeLists.txt samples: make find_package(Zephyr...) REQUIRED 2020-05-29 10:47:25 +02:00
prj.conf
README.rst boards: arm: nrf51_pca10028: rename board to nrf51dk_nrf51422 2020-03-24 11:45:27 +01:00
sample.yaml samples: clean test identifiers 2020-05-11 17:00:26 +02:00

.. _nvs-sample:

NVS: Non-Volatile Storage
#########################

Overview
********

This is a simple application demonstrating use of the NVS
module for non-volatile (flash) storage.  In this application,
a counter is incremented on every reboot and stored in flash,
the application reboots, and the reboot counter data is retrieved.

Requirements
************

* A board with flash support

Building and Running
********************

This sample can be found under :zephyr_file:`samples/subsys/nvs` in the Zephyr tree.

The sample can be build for several platforms, the following commands build the
application for the nrf51dk_nrf51422 board.

.. zephyr-app-commands::
   :zephyr-app: samples/subsys/nvs
   :board: nrf51dk_nrf51422
   :goals: build flash
   :compact:

After flashing the image to the board the output on the console shows the
reboot counter and the boards reboots several times to show the reboot counter
is incremented.

Sample Output
=============

.. code-block:: console

   ***** Booting Zephyr OS v1.12.0-rc1-176-gf091be783 *****
   [fs/nvs] [DBG] nvs_reinit: (Re)Initializing sectors
   [fs/nvs] [DBG] _nvs_sector_init: f->write_location set to c
   [fs/nvs] [INF] nvs_init: maximum storage length 256 byte
   [fs/nvs] [INF] nvs_init: write-align: 1, write-addr: c
   [fs/nvs] [INF] nvs_init: entry sector: 0, entry sector ID: 1
   No address found, adding 192.168.1.1 at id 1
   No key found, adding it at id 2
   No Reboot counter found, adding it at id 3
   Id: 4 not found, adding it
   Longarray not found, adding it as id 4
   Reboot counter history: ...0
   Oldest reboot counter: 0
   Rebooting in ...5...4...3...2...1
   ***** Booting Zephyr OS v1.12.0-rc1-176-gf091be783 *****
   [fs/nvs] [INF] nvs_init: maximum storage length 256 byte
   [fs/nvs] [INF] nvs_init: write-align: 1, write-addr: c7
   [fs/nvs] [INF] nvs_init: entry sector: 0, entry sector ID: 1
   Entry: 1, Address: 192.168.1.1
   Id: 2, Key: ff fe fd fc fb fa f9 f8
   Id: 3, Reboot_counter: 1
   Id: 4, Data: DATA
   Id: 5, Longarray: 0 1 2 3 4 5 6 7 8 9 a b c d e f 10 11 12 13 14 15 16 17 18
   Reboot counter history: ...1...0
   Oldest reboot counter: 0
   Rebooting in ...5...4...3...2...1
   ...